Methods and systems for reducing spillover by analyzing sound pressure levels

ABSTRACT

Methods, apparatus, and articles of manufacture for reducing spillover in a media monitoring system are disclosed. An example method includes identifying media associated with media monitoring data. The media monitoring data is received from a first meter associated with a first media presentation device. The example method includes identifying an expected sound pressure level associated with the first meter. The example method includes comparing the expected sound pressure level to an actual sound pressure level collected from the media by the first meter to determine if spillover occurred. The example method includes crediting the media as a media exposure if spillover did not occur.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to media monitoring and, moreparticularly, to methods and systems for reducing spillover by analyzingsound pressure levels.

BACKGROUND

Audience measurement of media, such as television, music, movies, radio,Internet websites, streaming media, etc., is typically carried out bymonitoring media exposure of panelists that are statistically selectedto represent particular demographic groups. Using various statisticalmethods, the captured media exposure data is processed to determine thesize and demographic composition of the audience(s) for programs ofinterest. The audience size and demographic information is valuable toadvertisers, broadcasters and/or other entities. For example, audiencesize and demographic information is a factor in the placement ofadvertisements, as well as a factor in valuing commercial time slotsduring a particular program.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example system including an example spillovermanager implemented in accordance with the teachings of this disclosureto manage spillover to reduce media monitoring inaccuracies in thesystem.

FIG. 2 illustrates an example implementation of an example mediaidentifying meter of FIG. 1.

FIG. 3 illustrates an example implementation of the example spillovermanager of FIG. 1.

FIG. 4 is a flow diagram representative of example machine readableinstructions that may be executed to implement the example spillovermanager of FIGS. 1 and/or 3.

FIG. 5 is a flow diagram representative of example machine readableinstructions that may be executed to implement the example mediaidentifying meter of FIGS. 1 and/or 2.

FIG. 6 is another flow diagram representative of example machinereadable instructions that may be executed to implement the examplespillover manager of FIGS. 1 and/or 3.

FIG. 7 is a block diagram of an example processor platform that may beused to execute the instructions of FIGS. 4, 5, and/or 6 to implementthe example media identifying meter 106 of FIG. 2, the example spillovermanager of FIG. 3, and/or, more generally, the example system of FIG. 1.

DETAILED DESCRIPTION

Audience measurement companies enlist persons to participate inmeasurement panels. Such persons (e.g., panelists) agree to allow theaudience measurement company to measure their exposure to media (e.g.,television programming, radio programming, Internet, advertising,signage, outdoor advertising, etc.). In order to associate mediamonitoring data (i.e., data reflecting media presentation) with panelistdemographics, the audience measurement company monitors media device(s)and/or panelist(s) using meters.

In some examples, meters (e.g., stationary meters) are placed withand/or near media presentation devices (e.g., televisions, stereos,speakers, computers, etc.) within a home or household. For example, ameter may be placed in a room with a television and another meter may beplaced in a different room with another television. In some examples,personal portable metering devices (PPMs), which are also known asportable metering devices or portable personal (or people) meters, areused to monitor media exposure of panelists. A PPM is an electronicdevice that is typically worn (e.g., clipped to a belt or other apparel)or carried by a panelist. The term “meter” as used herein refersgenerally to stationary meters and/or portable meters.

In general, media identifying meters are configured to use a variety oftechniques to monitor media presentations at media presentation devicesand/or exposure of panelists to media presentations. For example, onetechnique for monitoring media exposure involves detecting or collectingmedia identifying information (e.g., codes (e.g., watermarks),signatures, etc.) from media signals (e.g., audio and/or video signals)that are emitted or presented by media presentation devices.

As media (e.g., content and/or advertisements) is presented, a mediaidentifying meter may receive media signals (e.g., via a microphone)associated with the media and may detect media (e.g., audio and/orvideo) information associated with the media to generate mediamonitoring data. In general, media monitoring data may include anyinformation that is representative of (or associated with) media and/orthat may be used to identify a particular media presentation (e.g., asong, a television program, a movie, a video game, an advertisement,etc.). For example, the media monitoring data may include signaturesthat are collected or generated by the media identifying meter based onthe media, audio codes that are broadcast simultaneously with (e.g.,embedded in) the media, etc. Each media identifying meter may receivedifferent media signals based on the media presented (e.g., tuned) onthe media presentation devices to which panelists are exposed.

Media monitoring systems may also include one or more people meters toidentify panelists in a monitored audience. Identifying the panelists inthe audience allows mapping of their demographics to the media.Panelists provide their demographic information when they agree to bemonitored by the audience measurement system. Any method of peoplemetering may be employed. For example, the people metering may be activein that it requires panelists to self-identify by, for instance,entering an identifier corresponding to their name, or it may be passivein that electronics (e.g., video cameras) may be used to identify and/orcount persons in the audience. See U.S. Pat. No. 7,609,853, which ishereby incorporated by reference herein in its entirety for an examplepeople metering solution.

A panelist home may present unique monitoring challenges to the mediaidentifying meters. For example, a panelist home often includes multiplemedia presentation devices, each configured to present media to specificviewing and/or listening areas located within the home. Known mediaidentifying meters that are located in one of the viewing and/orlistening areas are typically configured to detect any media beingpresented in the viewing and/or listening area and to credit the mediaas having been presented. Thus, known media identifying meters operateon the premise that any media detected by the media identifying meter ismedia that was presented in that particular viewing and/or listeningarea. However, in some cases, a media identifying meter may detect mediathat is emitted by a media presentation device that is not locatedwithin the viewing or listening proximity of a panelist in the room withthe media identifying meter thereby causing the detected media to beimproperly credited to the panelist currently associated with themonitored area (via, for example, a people meter). The ability of themedia identifying meter to detect media being presented outside of theviewing and/or listening proximity of the panelist is referred to as“spillover” because the media being presented outside of the viewingand/or listening proximity of the panelist is “spilling over” into thearea occupied by the media identifying meter and may not actually fallwithin the attention of the panelist. Spillover may occur, for example,when a television in a particular room is powered off, but a mediaidentifying meter associated with that television detects media beingpresented on a media presentation device in a different room of thepanelist home or of an adjacent home (e.g., a neighbor's condominium orapartment). In such an example, the media identifying meter improperlycredits the media as being presented on the media presentation device itmonitors even though no such presentation occurred.

Another effect, referred to as “hijacking,” occurs when a mediaidentifying meter detects different media being presented at multiplemedia presentation devices at the same time. For example, a mediaidentifying meter in a kitchen may detect a particular media programbeing presented on a media presentation device in the kitchen, but themedia identifying meter may also detect a different media program thatis being presented on a different media presentation device in a livingroom. In such an example, the media presented by the media presentationdevice in the living room may, in some cases, have signals thatoverpower or “hijack” the signals associated with the media beingpresented by the media presentation device in the kitchen. As a result,the media identifying meter in the kitchen may inaccurately credit themedia being presented in the living room and fail to credit the mediabeing presented in the kitchen. In some examples, other difficultiessuch as varying volume levels, varying audio/video content type (e.g.,sparse, medium, rich, etc.), varying household transmissioncharacteristics due to open/closed doors, movement and/or placement offurniture, acoustic characteristics of room layouts, wall construction,floor coverings, ceiling heights, etc. may exacerbate these issues and,thus, lead to inaccurate media presentation detection by mediaidentifying meters.

Example methods and systems disclosed herein may be used to manage audiospillover and/or other sources of media monitoring inaccuracies in thecourse of presentations of media to more accurately assess the exposureof panelists to that media. Example methods and systems may be used toprevent audio spillover from adversely affecting results of mediamonitoring. Some example methods and systems analyze media monitoringdata to determine if audio spillover has occurred. In some suchexamples, if audio spillover has not occurred, the media is credited asactual media exposure (e.g., a panelist has been exposed to the media).If audio spillover has occurred, the media is not credited as an actualmedia exposure.

Example methods and systems disclosed herein detect signal spillover byanalyzing sound pressure levels associated with media presentations(e.g., sound pressure levels of audio signal waveforms representative ofmedia presentations). Sound pressure levels identify at what volumemedia presentations (e.g., content and/or advertisements) are beingpresented (e.g., how loud the media presentation is). Particular soundpressure levels may be expected from media presentations based on wherethe media presentations are occurring and/or when the mediapresentations are occurring. For example, quieter media presentations(e.g., with lower sound pressure levels) may be expected later at nightand/or when the media presentation is presented in a bedroom and loudermedia presentations (e.g., with higher sound pressure levels) may beexpected during the day and/or when the media presentation is presentedin a living room. A value of a sound pressure level expected from amedia presentation based on or dependent on a location of presentationand/or a time of presentation is referred to herein as an expected soundpressure level.

In some examples, a media identifying meter monitoring a mediapresentation from a proximate media presentation device (e.g., a devicein the same room as the meter) may analyze a waveform of the mediapresentation and calculate an actual sound pressure level of thewaveform. In some examples, the actual sound pressure level is comparedto the expected sound pressure level to determine if spillover hasoccurred. For example, the actual sound pressure level may be differentfrom (e.g., smaller than) the expected sound pressure level when theaudio has traveled a larger distance than expected between the mediaidentifying meter and the media presentation device it monitors, theaudio has been transmitted through different rooms (e.g., the signal hasbounced off of walls, traveled through a wall, a ceiling, or a floor,etc.), etc. If the actual sound pressure level is sufficiently similarto the expected sound pressure level (e.g., within a threshold amount),it is determined that spillover has not occurred. If the actual soundpressure level is not sufficiently similar to the expected soundpressure level (e.g., within a threshold amount), it is determined thatspillover has occurred. In some examples, when it is determined thatspillover has occurred, the media presentation is not credited as anactual media exposure.

An example method disclosed herein includes identifying media based onmedia monitoring data. The media monitoring data is received from afirst media identifying meter associated with a first media presentationdevice. The example method includes identifying an expected soundpressure level associated with the first meter. The example methodincludes comparing the expected sound pressure level to an actual soundpressure level collected from the media by the first meter to determineif spillover occurred. The example method includes crediting the mediaas a media exposure if spillover did not occur.

An example spillover manager disclosed herein includes a sound pressurelevel comparator to identify an expected sound pressure level for mediaassociated with media monitoring data received from a meter associatedwith a media presentation device. The example sound pressure levelcomparator is to compare the expected sound pressure level to an actualsound pressure level to determine if spillover occurred. The actualsound pressure level is based on a sample of the media collected by themeter. The example spillover manager includes a media creditor to creditthe media with an exposure if spillover did not occur and to not creditthe media with an exposure if spillover did occur.

An example tangible computer readable storage medium disclosed hereincomprises instructions that, when executed, cause a computing device toidentify media associated with media monitoring data. The mediamonitoring data is received from a first meter associated with a firstmedia presentation device. The example instructions cause the computingdevice to identify an expected sound pressure level associated with thefirst meter. The example instructions cause the computing device tocompare the expected sound pressure level to an actual sound pressurelevel collected from the media by the first meter to determine ifspillover occurred. The example instructions cause the computing deviceto credit the media as a media exposure if spillover did not occur.

FIG. 1 illustrates an example media monitoring system 100 in an exampleenvironment of use. The example of FIG. 1 includes an example spillovermanager 102 implemented in accordance with the teachings of thisdisclosure to manage spillover to reduce (e.g., prevent) mediamonitoring inaccuracies in the media monitoring system 100. In theillustrated example, a first media identifying meter 106 monitors mediapresented by a first media presentation device 108 in a first room 110and a second media identifying meter 112 monitors media presented on asecond media presentation device 114 in a second room 116. Either orboth of the first and second media presentation devices 108, 114 may be,for example, a television, a radio, a computer, a stereo system, a DVDplayer, a game console, etc. Media may include, for example, any form ofcontent, television programming, radio programming, movies, songs, anyform of advertisements, Internet information such as websites and/orstreaming media, and/or any other video information, audio information,still image information, and/or computer information to which a panelist(e.g., an example panelist 118) may be exposed. While two rooms 110,116, two media presentation devices 108, 114, and two media identifyingmeters 106, 112 are shown in the example of FIG. 1, any number and/ortype(s) of rooms, any number and/or type(s) of media presentationdevices, and/or any number and/or type(s) of meters (including, forexample, people meters) in any configuration and/or spatial relationshipmay be implemented in the example system 100.

In the illustrated example, to respectively monitor media presented onthe first and second media presentation devices 108, 114, the first andsecond media identifying meters 106, 112 process media signals (orportions thereof such as audio portions of the media signals)respectively output by the first and second media presentation devices108, 114 to extract codes and/or metadata, and/or to generate signaturesfor use in identifying the media and/or a station (e.g., a broadcaster)originating the media. The first media identifying meter 106 of theillustrated example is intended to monitor the first media presentationdevice 108 and to not monitor the second media presentation device 114.The second media identifying meter 112 is intended to monitor the secondmedia presentation device 114 and to not monitor the first mediapresentation device 108.

Identification codes, such as watermarks, ancillary codes, etc. may beembedded within or otherwise transmitted with media signals.Identification codes are data that are inserted into media (e.g., audioor video) to uniquely identify broadcasters and/or media (e.g., contentor advertisements), and/or are carried with the media for anotherpurpose such as tuning (e.g., packet identifier headers (“PIDs”) usedfor digital broadcasting). Codes are typically extracted using adecoding operation.

Signatures are a representation of one or more characteristic(s) of themedia signal (e.g., a characteristic of the frequency spectrum of thesignal). Signatures can be thought of as fingerprints. They aretypically not dependent upon insertion of identification codes in themedia, but instead preferably reflect an inherent characteristic of themedia and/or the media signal. Systems to utilize codes and/orsignatures for audience measurement are long known. See, for example,Thomas, U.S. Pat. No. 5,481,294, which is hereby incorporated byreference in its entirety. Codes, metadata, signatures, channelidentifiers (e.g., tuned channel numbers), etc. collected and/orgenerated by the first or second media identifying meters 106, 112 foruse in identifying media and/or a station transmitting media may bereferred to generally as “media monitoring data.”

In the illustrated example, media monitoring data collected by the firstmedia identifying meter 106 and/or the second media identifying meter112 is transferred to the home processing system 104 for furtherprocessing. The first and second media identifying meters 106, 112 maybe communicatively coupled with the home processing system 104 viawireless and/or hardwired communications and may periodically and/oraperiodically communicate collected media monitoring information to thehome processing system 104. People meters 128, 130 may likewise becommunicatively coupled with the home processing system 104 toperiodically and/or aperiodically forward people identification data tothe home processing system 104.

In the illustrated example, the home processing system 104 iscommunicatively coupled to a remotely located central data collectionfacility 120 via a network 122. The example home processing system 104of FIG. 1 transfers collected media monitoring data to the centralfacility 120 for further processing. The central facility 120 of theillustrated example collects and/or stores, for example, mediamonitoring data that is collected by multiple media monitoring devicessuch as, for example, the media identifying meters 106, 112, and/ordemographic information that is collected by people meters, located atmultiple panelist locations. The central facility 120 may be, forexample, a facility associated with an audience measurement entity suchas The Nielsen Company (US), LLC or any affiliate of The Nielsen Company(US), LLC. The central facility 120 of the illustrated example includesa server 124 and a database 126 that may be implemented using anysuitable processor, memory and/or data storage apparatus such as thatshown in FIG. 7. In some examples, the home processing system 104 islocated in the central facility 120.

The network 122 of the illustrated example is used to communicateinformation and/or data between the example home processing system 104and the central facility 120. The network 122 may be implemented usingany type(s) of public and/or private network(s) such as, but not limitedto, the Internet, a telephone network, a cellular network, a local areanetwork (“LAN”), a cable network, and/or a wireless network. To enablecommunication via the network 122, the home processing system 104 of theillustrated example includes a communication interface that enablesconnection to an Ethernet, a digital subscriber line (“DSL”), atelephone line, a coaxial cable, and/or any wireless connection, etc.

Some known methods for measuring media exposure or presentation track orlog media presentations to which a panelist is exposed and award a mediaexposure credit to a media presentation whenever the panelist is in thevicinity of that media presentation. However, some such methods mayproduce inconsistent or inaccurate monitoring results due to spilloverthat occurs. For example, within the example environment illustrated inFIG. 1, spillover may occur when the first media presentation device 108is powered off (e.g., is not presenting media), but the first mediaidentifying meter 106 associated with the first media presentationdevice 108 detects media being presented by the second mediapresentation device 114. In such an example, the first media identifyingmeter 106 will incorrectly credit the media presented at the secondmedia presentation device 114 as being presented to the panelist 118.Recording media data that has spilled over from another space (e.g., theroom 116) may result in an inaccurate representation of the mediapresented to the panelist 118. In some such examples, the panelist 118may not even know or be aware of the media, but the electronics of themedia identifying meter 106 may still be sensitive enough to detect acode in the media presented by the second media presentation device 114.

The spillover manager 102 of the illustrated example is used to managespillover to reduce (e.g., prevent) media monitoring inaccuracies in theexample system 100 of FIG. 1. The example spillover manager 102 of FIG.1 receives media monitoring data from the first example mediaidentifying meter 106 and/or the second example media identifying meter112 and analyzes the media monitoring data to determine if spillover hasoccurred. In the illustrated example, if the example spillover manager102 detects spillover associated with the first media identifying meter106 and/or the second media identifying meter 112, the media identifiedin the media monitoring data is not credited as actual media exposurefor the meter/monitored media presentation device that experienced thespillover and the media monitoring data associated with the uncreditedmedia is discarded and/or marked as invalid. In the illustrated example,if the example spillover manager 102 does not detect spilloverassociated with the first media identifying meter 106 and/or the secondmedia identifying meter 112, the media identified in the mediamonitoring data is credited as actual media exposure(s). In theillustrated example, the spillover manager 102 sends media monitoringdata associated with credited media to the example central facility 120.In some examples, the spillover manager 102 labels portion(s) of themedia monitoring data as either associated with credited or uncreditedmedia and sends the identified media monitoring data to the examplecentral facility 120.

In the illustrated example, the spillover manager 102 detects spilloverby analyzing sound pressure levels associated with media presentations.Sound pressure levels identify the volume at which media presentations(e.g., content and/or advertisements) are being presented (e.g., howloud the media presentation is). Particular sound pressure levels may beexpected from media presentations based on where the media presentationsare occurring and/or when the media presentations are occurring. A soundpressure level expected from a media presentation based on a location ofpresentation and/or a time of presentation may be referred to as anexpected sound pressure level. The spillover manager 102 of theillustrated example stores and/or accesses (e.g., from the centralfacility 120) expected sound pressure levels for use in spilloverdetection. In some examples, for each media identifying meter in a home(e.g., the first and second media identifying meters 106, 112), one ormore expected sound pressure levels are stored based on days and/ortimes of media presentations being monitored by the meters. Expectedsound pressure levels may be calculated and/or determined during, forexample, a training period where values of sound pressure levels forparticular meters and/or areas of homes at particular days and/or timesare gathered and analyzed for use in spillover detection.

In the illustrated example, the first and second media identifyingmeters 106, 112 receive media signals (e.g., audio) associated withmedia presentations (e.g., via microphones). In the illustrated example,in addition to collecting media monitoring data from the received mediasignals, the example first and second media identifying meters 106, 112analyze samples of the media (e.g., audio waveforms of the mediasignals) and calculate sound pressure levels of the audio waveforms. Thesound pressure levels calculated by the example first and second mediaidentifying meters 106, 112 are referred to as “actual sound pressurelevels” because they represent the sound pressure levels of the audiowaveforms after they have been presented on the first or second mediapresentation devices 108, 114 and received at the corresponding firstand/or second media identifying meters 106, 112. The first and secondmedia identifying meters 106, 112 of the illustrated example timestampthe media monitoring data and the actual sound pressure levels and storethe timestamped data in association with a meter identifier of the firstor second media identifying meters 106, 112. The meter identifieridentifies the particular media identifying meter (e.g., the mediaidentifying meter 106 or the media identifying meter 112) collecting themedia monitoring data. This meter identifier is important in thespillover determination and in aligning people identifying datacollected by the people meters 128, 130 with the media identifyinginformation collected by the media identifying meters 106, 112. Themeter identifier may be an alphanumeric identification code (e.g., aseries of letters and/or numbers) that may be used to identify the mediaidentifying meter 106 or the media identifying meter 112. The first andsecond media identifying meters 106, 112 send the timestamped mediamonitoring data and actual sound pressure level data with the meteridentifier to the example spillover manager 102 for analysis. In someexamples, the sound pressure levels are not generated at the mediaidentifying meters 106, 112, but instead are generated at the spillovermanager 102.

The spillover manager 102 of the illustrated example identifies expectedsound pressure levels to be compared with the actual sound pressurelevels received from the first and second media identifying meters 106,112. To identify expected sound pressure levels, the spillover manager102 of the illustrated example uses the meter identifier and/or thetimestamp associated with the actual sound pressure level data (e.g.,the spillover manager 102 uses the meter identifier and/or the timestampto access a table storing the expected sound pressure levels). Anexample table is illustrated below.

TABLE 1 EXPECTED SOUND METER IDENTIFIER TIME PRESSURE LEVEL Livingroom 6:00 am-11:59 am 55 dB Livingroom 12:00 pm-7:59 pm  65 dB Livingroom8:00 pm-5:59 am 45 dB Bedroom  6:00 am-11:59 am 60 dB Bedroom 12:00pm-7:59 pm  60 dB Bedroom 8:00 pm-5:59 am 40 dB

The spillover manager 102 of the illustrated example finds an expectedsound pressure level for a meter identified by the meter identifier at atime identified by the timestamp. For example, the spillover manager 102may identify a particular expected sound pressure level representativeof a media presentation being presented in a bedroom (e.g., the room110) at 11:00 pm (e.g., 40 dB).

To determine if spillover occurred, the spillover manager 102 of theillustrated example compares the expected sound pressure level for theidentified meter and/or time to the actual sound pressure levelcollected and/or determined by the example first and/or second mediaidentifying meter 106, 112 that collected the media identification databeing analyzed. If the actual sound pressure level is sufficientlysimilar to the expected sound pressure level (e.g., within a thresholdamount) to conclude that the media in question originated in the sameroom as the media identifying meter that detected it, the examplespillover manager 102 determines that spillover did not occur for thecorresponding media identification event. Thus, the person(s) (e.g., thepanelist 118) identified as present by a first people meter 128associated with the corresponding media identifying meter that collectedthe data (e.g., the first media identifying meter 106/first mediapresentation device 108 or a second people meter 130 associated with thesecond media identifying meter 112/second media presentation device 114)are credited as having been exposed to the media. If the actual soundpressure level is not sufficiently similar to the expected soundpressure level (e.g., within a threshold amount) to conclude that thecorresponding media originated from a media presentation device intendedto be monitored by the media identifying meter in question, the examplespillover manager 102 determines that spillover occurred for thecorresponding media identification event. Thus, the persons (e.g., thepanelist 118) identified as present by the corresponding people meter(e.g., the first people meter 128 or the second people meter 130) arenot credited as having been exposed to the media. In other words, whenthe example spillover manager 102 of FIG. 1 determines that spilloverhas occurred, the media is not credited with an actual media exposure atthe corresponding media presentation device (e.g., media presentationdevices 108, 114).

For example, when the first example media identifying meter 106 receivesa media signal, it determines an actual sound pressure level for thereceived media signal, in addition to collecting media monitoring datafor the received media signal. In such an example, the first mediaidentifying meter 106 timestamps the actual sound pressure level data.It then sends the actual sound pressure level data and the mediamonitoring data along with a meter identifier of the first example mediaidentifying meter 106 to the example spillover manager 102. The examplespillover manager 102 of FIG. 1 identifies the media identifying meter106 from the meter identifier, identifies a time from the timestamp, andaccesses (e.g., looks up in a local database or cache, retrieves from aremote database such as a database at the central facility 120) anexpected sound pressure level associated with or dependent on the mediaidentifying meter 106 and/or the time. If the actual sound pressurelevel is sufficiently similar to the expected sound pressure level, theexample spillover manager 102 of FIG. 1 assumes the media was presentedon the first example media presentation device 108 corresponding to thefirst media identifying meter 106 (i.e., the media identifying meterthat provided the media monitoring data under analysis) and credits themedia as an actual media exposure at the corresponding mediapresentation device. Thus, the person(s) identified as present by thefirst people meter 128 (e.g., the panelist 118) are credited as havingbeen exposed to the media. If the actual sound pressure level is notsufficiently similar to the expected sound pressure level, the examplespillover manager 102 assumes the media was not presented on the examplemedia presentation device 108 (e.g., the media was presented on themedia presentation device 114 and the media signal spilled over to theexample media identifying meter 106), and does not credit the media asan actual media exposure (e.g., does not credit the media with exposureto the panelist 118).

While the spillover manager 102 of the illustrated example is shownwithin the example home processing system 104, the spillover manager 102may be implemented at the first media identifying meter 106, the secondmedia identifying meter 112, and/or at the central facility 120.

FIG. 2 is a block diagram of an example implementation of the firstand/or second media identifying meters 106, 112 of FIG. 1. The mediaidentifying meter 106, 112 of the illustrated example receives mediasignals (e.g., audio signals) from one or more media presentationdevices (e.g., the first or second media presentation device 108, 114 ofFIG. 1). In the illustrated example, the media identifying meter 106,112 is used to collect media monitoring data (e.g., to extract and/oranalyze codes and/or signatures from media signals output by acorresponding media presentation device 108, 114). The media identifyingmeter 106, 112 also detects sound pressure levels of the media signals.Thus, the media identifying meter 106, 112 of the illustrated example isused to collect, aggregate, locally process, and/or transfer mediamonitoring data and/or sound pressure level data to the spillovermanager 102 of FIG. 1. The media identifying meter 106, 112 of theillustrated example includes an example input 202, an example codecollector 204, an example signature generator 206, example control logic208, an example timestamper 210, an example database 212, an exampletransmitter 214, and an example sound pressure level calculator 216.

In the illustrated example, the input 202 is a microphone exposed toambient sound and serves to collect audio signals output by monitoredmedia presentation devices (e.g., the media presentation device 108). Tocollect media monitoring data associated with the audio signals, theinput 202 of the illustrated example passes a received audio signal tothe code collector 204 and/or the signature generator 206. The codecollector 204 of the illustrated example extracts codes and/or thesignature generator 206 generates signatures from the signal to identifybroadcasters, channels, stations, and/or programs. The control logic 208of the illustrated example is used to control the code collector 204and/or the signature generator 206 to cause collection of a code, asignature, or both a code and a signature. The identified codes and/orsignatures (e.g., the media monitoring data) are timestamped at theexample timestamper 210, are stored in the example database 212, and aretransmitted by the example transmitter 214 to the spillover manager 102at the home processing system 104. Although the example of FIG. 2collects codes and/or signatures from audio signals, codes or signaturescan additionally or alternatively be collected from other portion(s) ofthe signal (e.g., from the video portion).

The input 202 of the illustrated example also passes the received audiosignal to the example sound pressure level calculator 216. The soundpressure level calculator 216 of the illustrated example calculates asound pressure level of the received audio signal by taking alogarithmic measure of a measured root mean square (RMS) sound pressureof the audio signal relative to a reference sound pressure. In someexamples, the reference sound pressure is 20 micro-Pascals RMS (μPaRMS), which is considered a threshold of human hearing. An example soundpressure level for a media presentation is 60 decibels (dB). An exampleequation to calculate a sound pressure level (L_(p)) is illustratedbelow.

$L_{p} = {20\mspace{14mu} {\log_{10}\left( \frac{p_{rms}}{p_{ref}} \right)}{dB}}$

The sound pressure level calculated by the example sound pressure levelcalculator 216 is referred to as the actual sound pressure level. Theactual sound pressure level is timestamped by the example timestamper210. The timestamped actual sound pressure level is stored at theexample database 212 in association with a meter identifier to identifythe media identifying meter 106, 112 that detected the sound pressurelevel. The meter identifier identifies the particular media identifyingmeter (e.g., the media identifying meter 106 or the media identifyingmeter 112) collecting the media monitoring data and calculating theactual sound pressure level data. The meter identifier may be anidentification code (e.g., a series of letters and/or numbers) that maybe used to identify the media identifying meter 106 or the mediaidentifying meter 112. The timestamped actual sound pressure level data(in association with the meter identifier) is transmitted by the exampletransmitter 214 to the example spillover manager 102 with the mediamonitoring data.

While an example manner of implementing the media identifying meter 106,112 of FIG. 1 is illustrated in FIG. 2, one or more of the elements,processes and/or devices illustrated in FIG. 2 may be combined, divided,re-arranged, omitted, eliminated and/or implemented in any other way.Further, the example input 202, the example code collector 204, theexample signature collector 206, the example control logic 208, theexample timestamper 210, the example database 212, the exampletransmitter 214, the example sound pressure level calculator 216,and/or, more generally, the example media identifying meter 106, 112 ofFIG. 1 may be implemented by hardware, software, firmware and/or anycombination of hardware, software and/or firmware. Thus, for example,any of the example input 202, the example code collector 204, theexample signature collector 206, the example control logic 208, theexample timestamper 210, the example database 212, the exampletransmitter 214, the example sound pressure level calculator 216,and/or, more generally, the example media identifying meter 106, 112could be implemented by one or more circuit(s), programmableprocessor(s), application specific integrated circuit(s) (ASIC(s)),programmable logic device(s) (PLD(s)) and/or field programmable logicdevice(s) (FPLD(s)), etc. When reading any of the apparatus or systemclaims of this patent to cover a purely software and/or firmwareimplementation, at least one of the example input 202, the example codecollector 204, the example signature collector 206, the example controllogic 208, the example timestamper 210, the example database 212, theexample transmitter 214, the example sound pressure level calculator216, and/or the example media identifying meter 106, 112 are herebyexpressly defined to include a tangible computer readable storage deviceor storage disc such as a memory, DVD, CD, Blu-ray, etc. storing thesoftware and/or firmware. Further still, the example media identifyingmeter 106, 112 of FIG. 1 may include one or more elements, processesand/or devices in addition to, or instead of, those illustrated in FIG.2, and/or may include more than one of any or all of the illustratedelements, processes and devices.

FIG. 3 is a block diagram of an example implementation of the examplespillover manager 102 of FIG. 1. The spillover manager 102 of theillustrated example receives media monitoring data and actual soundpressure level data from one or more media identifying meter(s) (e.g.,the media identifying meters 106, 112 of FIG. 1). In the illustratedexample, the spillover manager 102 uses the media monitoring data andthe actual sound pressure level data to determine whether spilloveroccurred and, based on that spillover determination, whether identifiedmedia programs are to be credited with actual exposure to a panelist.The spillover manager 102 of the illustrated example is used to transfercredited media monitoring data (e.g., media monitoring data associatedwith credited media programs) to the central facility 120 of FIG. 1. Thespillover manager 102 of the illustrated example includes an examplesound pressure level comparator 302, an example sound pressure leveldatabase 304, an example media creditor 306, and an example transmitter308.

The sound pressure level comparator 302 of the illustrated examplereceives media monitoring data and actual sound pressure levels from themedia identifying meter(s) (e.g., the first and second media identifyingmeters 106, 112 of FIG. 1). The sound pressure level comparator 302 ofthe illustrated example identifies expected sound pressure level data tobe compared with the actual sound pressure level data. To identify therelevant expected sound pressure level data stored in the example soundpressure level database 304, the sound pressure level comparator 302 ofthe illustrated example uses the meter identifier and/or the timestampassociated with the actual sound pressure levels.

For each media identifying meter in a home (e.g., the first and secondmedia identifying meters 106, 112), the example sound pressure leveldatabase 304 stores one or more expected sound pressure levels based ondays and/or times of media presentations being monitored by the mediaidentifying meters. For example, for each particular media identifyingmeter, the example sound pressure level database 304 stores an expectedsound pressure level for particular day(s) and/or time(s). Expectedsound pressure levels may be calculated and/or determined by the examplespillover manager 102 at the example spillover manager 102 to monitorthe example system 100 of FIG. 1 and/or the expected sound pressurelevels may be calculated at, for example, a central facility (e.g., thecentral facility 120 of FIG. 1). In some examples, the spillover manager102 may be implemented at the central facility 120 to process datacollected from various meters. Additionally or alternatively, the soundpressure level database 304 may be located at the central facility andthe spillover manager 102 may query the database 304 via the network122.

The sound pressure level comparator 302 of the illustrated example findsan expected sound pressure level in the example sound pressure leveldatabase 304 corresponding to an actual sound pressure level byidentifying a media identifying meter using the meter identifier and byidentifying a time of presentation of a media presentation using thetimestamp (e.g., using a table such as Table 1 above). Once the soundpressure level comparator 302 obtains the expected sound pressure levelassociated with the media identifying meter and/or time of presentation,the sound pressure level comparator 302 of the illustrated examplecompares the expected sound pressure level to the actual sound pressurelevel.

If the actual sound pressure level is sufficiently similar to theexpected sound pressure level (e.g., if a difference between the actualsound pressure level and the expected sound pressure level is within athreshold amount), the sound pressure level comparator 302 of theillustrated example determines spillover did not occur and instructs theexample media creditor 306 to credit the media as an actual mediaexposure. If the actual sound pressure level is not sufficiently similarto the expected sound pressure level (e.g., if the difference betweenthe actual sound pressure level (such as 55 dB) and the expected soundpressure level (such as 60 dB) is not within the threshold amount (suchas 2 dB)), the sound pressure level comparator 302 of the illustratedexample determines that spillover did occur and instructs the examplemedia creditor 306 to not credit the media as an actual media exposure.

The media creditor 306 of the illustrated example credits/does notcredit media as actual media exposure based on the output of the examplesound pressure level comparator 302. If the example sound pressure levelcomparator 302 determines that spillover did not occur, the mediacreditor 306 of the illustrated example marks the media monitoring dataassociated with the media as credited. If the example sound pressurelevel comparator 302 determines that spillover did occur, the mediacreditor 306 of the illustrated example discards the media monitoringdata associated with the media. In some examples, rather than discardingthe media monitoring data associated with the media that is notcredited, the example media creditor 306 marks the media monitoring dataassociated with the media as uncredited.

The transmitter 308 of the illustrated example transmits the creditedmedia monitoring data to a central facility (e.g., the central facility120 of FIG. 1) for further processing. In some examples, where theexample media creditor 306 does not discard the uncredited mediamonitoring data, the example transmitter 308 transmits the creditedmedia monitoring data and the uncredited media monitoring data to thecentral facility 120 for further processing.

While an example manner of implementing the spillover manager 102 ofFIG. 1 is illustrated in FIG. 3, one or more of the elements, processesand/or devices illustrated in FIG. 3 may be combined, divided,re-arranged, omitted, eliminated and/or implemented in any other way.Further, the example sound pressure level comparator 302, the examplesound pressure level database 304, the example media creditor 306, theexample transmitter 308, and/or, more generally, the example spillovermanager 102 of FIG. 1 may be implemented by hardware, software, firmwareand/or any combination of hardware, software and/or firmware. Thus, forexample, any of the example sound pressure level comparator 302, theexample sound pressure level database 304, the example media creditor306, the example transmitter 308, and/or, more generally, the examplespillover manager 102 could be implemented by one or more circuit(s),programmable processor(s), application specific integrated circuit(s)(ASIC(s)), programmable logic device(s) (PLD(s)) and/or fieldprogrammable logic device(s) (FPLD(s)), etc. When reading any of theapparatus or system claims of this patent to cover a purely softwareand/or firmware implementation, at least one of the example soundpressure level comparator 302, the example sound pressure level database304, the example media creditor 306, the example transmitter 308, and/orthe example spillover manager 102 are hereby expressly defined toinclude a tangible computer readable storage device or storage disc suchas a memory, DVD, CD, Blu-ray, etc. storing the software and/orfirmware. Further still, the example spillover manager 102 of FIG. 1 mayinclude one or more elements, processes and/or devices in addition to,or instead of, those illustrated in FIG. 3, and/or may include more thanone of any or all of the illustrated elements, processes and devices.

Flowcharts representative of example machine readable instructions forimplementing the media identifying meter 106, 112 of FIGS. 1 and 2 andthe spillover manager 102 of FIGS. 1 and 3 are shown in FIGS. 4, 5, and6. In this example, the machine readable instructions comprise a programfor execution by a processor such as the processor 712 shown in theexample processor platform 700 discussed below in connection with FIG.7. The program may be embodied in software stored on a tangible computerreadable storage medium such as a CD-ROM, a floppy disk, a hard drive, adigital versatile disk (DVD), a Blu-ray disk, or a memory associatedwith the processor 712, but the entire program and/or parts thereofcould alternatively be executed by a device other than the processor 712and/or embodied in firmware or dedicated hardware. Further, although theexample program is described with reference to the flowchartsillustrated in FIGS. 4, 5, and 6, many other methods of implementing theexample media identifying meter 106, 112 and the example spillovermanager 102 may alternatively be used. For example, the order ofexecution of the blocks may be changed, and/or some of the blocksdescribed may be changed, eliminated, or combined.

As mentioned above, the example processes of FIGS. 4, 5, and 6 may beimplemented using coded instructions (e.g., computer and/or machinereadable instructions) stored on a tangible computer readable storagemedium such as a hard disk drive, a flash memory, a read-only memory(ROM), a compact disk (CD), a digital versatile disk (DVD), a cache, arandom-access memory (RAM) and/or any other storage device or storagedisk in which information is stored for any duration (e.g., for extendedtime periods, permanently, for brief instances, for temporarilybuffering, and/or for caching of the information). As used herein, theterm tangible computer readable storage medium is expressly defined toinclude any type of computer readable storage device and/or storage diskand to exclude propagating signals. As used herein, “tangible computerreadable storage medium” and “tangible machine readable storage medium”are used interchangeably. Additionally or alternatively, the exampleprocesses of FIGS. 4, 5, and 6 may be implemented using codedinstructions (e.g., computer and/or machine readable instructions)stored on a non-transitory computer and/or machine readable medium suchas a hard disk drive, a flash memory, a read-only memory, a compactdisk, a digital versatile disk, a cache, a random-access memory and/orany other storage device or storage disk in which information is storedfor any duration (e.g., for extended time periods, permanently, forbrief instances, for temporarily buffering, and/or for caching of theinformation). As used herein, the term non-transitory computer readablemedium is expressly defined to include any type of computer readabledevice or disc and to exclude propagating signals. As used herein, whenthe phrase “at least” is used as the transition term in a preamble of aclaim, it is open-ended in the same manner as the term “comprising” isopen ended.

FIG. 4 is a flow diagram representative of example machine readableinstructions that may be executed to implement the example spillovermanager 102 of FIG. 1 to manage audio spillover in the example system100 of FIG. 1. The spillover manager 102 of the illustrated example isused to manage spillover to reduce (e.g., prevent) media monitoringinaccuracies in the system 100.

The example spillover manager 102 determines if media monitoring datahas been received (block 402). The example spillover manager 102 is toreceive media monitoring data from one or more media identifyingmeter(s) (e.g., the first and/or second media identifying meters 106,112 of FIG. 1). The media monitoring data is representative of mediathat has been presented on one or more media presentation device(s)(e.g., the first and/or second media presentation devices 108, 114 ofFIG. 1). Control remains at block 402 until media monitoring data isreceived by the example spillover manager 102).

The example spillover manager 102 of the illustrated example analyzesthe media monitoring data to determine if spillover has occurred (block404). An example method to determine if spillover has occurred isdescribed below with reference to FIG. 6. If the example spillovermanager 102 detects spillover associated with the first and/or secondmedia identifying meters 106, 112 based on the media monitoring data,the media identified in the media monitoring data is not credited as anactual media exposure (block 406) and the media monitoring dataassociated with the uncredited media is discarded (block 408). Controlthen returns to block 402. In some examples, rather than discarding theuncredited media monitoring data, the example spillover manager 102identifies the media monitoring data as uncredited media and exports theuncredited media monitoring data to a central facility (e.g., theexample central facility 120).

If the example spillover manager 102 of the illustrated example does notdetect spillover associated with the first and/or the second mediaidentifying meter 106, 112, the media identified in the media monitoringdata is credited as an actual media exposure (block 410). The examplespillover manager 102 of the illustrated example exports mediamonitoring data associated with credited media to the example centralfacility 120 (block 412). Control then returns to block 402 when theinstructions are complete.

FIG. 5 is a flow diagram representative of example machine readableinstructions that may be executed to implement the example mediaidentifying meter 106, 112 of FIG. 1 to collect media monitoring dataand to calculate sound pressure levels. In the illustrated example, tocollect media monitoring data, the media identifying meter 106, 112extracts and/or analyzes codes and/or signatures from data and/orsignals received from one or more media presentation devices (e.g., thefirst and/or the second media presentation devices 108, 114 of FIG. 1).

Initially, the example input 202 obtains a signal (e.g., an audiosignal) from the one or more media presentation devices (e.g., the firstand/or the second media presentation devices 108, 114) (block 502). Theexample control logic 208 determines whether to collect a code orgenerate a signature from the signal obtained at the input 202 (block504). In the illustrated example, either a code is collected or asignature is generated from the signal. In other examples, both a codeand a signature are collected and/or generated.

If a code is to be collected, the example code collector 204 collects acode from the signal obtained at the input 202 (block 506). The examplecode collector 204 passes the collected code(s) to the timestamper 210.If a signature is to be generated, the signature generator 206 generatesa signature from the signal obtained at the input 202 (block 508). Theexample signature generator 206 passes the generated signature(s) to thetimestamper 210.

The example sound pressure level calculator 216 of the illustratedexample calculates a sound pressure level of the signal obtained at theinput 202 (block 510). The example sound pressure level calculator 216passes data representative of the actual sound pressure level to theexample timestamper 210. The example timestamper 210 timestamps thecollected codes and/or generated signatures and the actual soundpressure level (block 512). The example timestamper 210 passes thecollected codes and/or generated signatures and the actual soundpressure level to the example database 212. The example database 212stores the collected codes and/or generated signatures and the actualsound pressure level along with an identifier of the media identifyingmeter (e.g., the media identifying meter 106, 112 of FIG. 1) (block514). The example transmitter 214 periodically and/or aperiodicallytransmits the collected codes and/or generated signatures and the actualsound pressure level data along with the meter identifier to thespillover manager 102 of FIG. 1 (block 516). Control then returns toblock 502. In some examples, the media identifying meter 106, 112collects and timestamps samples of the audio, and periodically oraperiodically exports the timestamped data for analysis by the spillovermanager 102 (which may be located at the panelist site or at the centralfacility). In such examples, blocks 504-510 and 514 are not performed inthe media identifying meter 106, 112, and blocks 512 and 516 aremodified to operate on the received signal (as opposed to on codes,signatures, and/or sound pressure levels).

FIG. 6 is a flow diagram representative of example machine readableinstructions that may be executed to implement the example spillovermanager 102 of FIG. 3 to manage audio spillover in the example system100 of FIG. 1 using sound pressure levels. The spillover manager 102 ofthe illustrated example is used to manage spillover to reduce mediamonitoring inaccuracies in the system 100.

The example spillover manager 102 receives media monitoring data andactual sound pressure levels from one or more media identifying meter(s)(e.g., the first and/or second media identifying meters 106, 112 ofFIG. 1) (block 602). The example spillover manager 102 uses the mediamonitoring data and the actual sound pressure level data to determinewhether spillover occurred (e.g., in the example system 100 of FIG. 1)and whether media is to be credited with an actual media exposure event.

The example sound pressure level comparator 302 identifies a mediaidentifying meter associated with the actual sound pressure level (e.g.,using the meter identifier included with the actual sound pressurelevel) and/or a time associated with the actual sound pressure level(e.g., using the timestamp of the actual sound pressure level data)(block 604). Based on the meter identifier and/or the timestamp, theexample sound pressure level comparator 302 uses the example soundpressure level database 304 to identify an expected sound pressure levelassociated with the meter and the time at which the actual soundpressure level data was collected (block 606). For each mediaidentifying meter in a home (e.g., the first and second mediaidentifying meters 106, 112), the example sound pressure level database304 stores one or more expected sound pressure levels based on daysand/or times of media presentations being monitored by the correspondingmedia identifying meters (see, for example, Table 1 above). The soundpressure level comparator 302 of the illustrated example finds anexpected sound pressure level in the example sound pressure leveldatabase 304 corresponding to the actual sound pressure level byidentifying a media identifying meter using the meter identifier and byidentifying a time of presentation of the corresponding mediapresentation using the timestamp.

The example sound pressure level comparator 302 compares a differencebetween the expected sound pressure level and the actual sound pressurelevel (e.g., the actual sound pressure level received from the firstand/or the second media identifying meter 106, 112) to a threshold(block 608). If the difference between the actual sound pressure leveland the expected sound pressure level is not within the threshold amount(e.g., is greater than the threshold), the example sound pressure levelcomparator 302 determines that spillover did occur and instructs theexample media creditor 306 not to credit the media as an actual mediaexposure (block 610). If the example sound pressure level comparator 302determines that spillover did occur, the example media creditor 306discards the media monitoring data associated with the media (block612). Control then returns to block 602. In some examples, rather thandiscarding the media monitoring data associated with the media that isnot credited, the example media creditor 306 marks the media monitoringdata associated with the media as uncredited.

If the difference between the actual sound pressure level and theexpected sound pressure level is within a threshold amount (e.g., lessthan the threshold) (block 608), the example sound pressure levelcomparator 302 determines spillover did not occur and the example mediacreditor 306 credits the media as an actual media exposure (block 614).In particular, the example media creditor 306 marks the media monitoringdata associated with the media as credited (block 614). The exampletransmitter 308 transmits the credited media monitoring data to acentral facility (e.g., the central facility 120 of FIG. 1) for furtherprocessing (block 616). In some examples, where the example mediacreditor 306 does not discard the uncredited media monitoring data, theexample transmitter 308 transmits the credited media monitoring data andthe uncredited media monitoring data to the central facility 120 forfurther processing (block 616). Control then returns to block 602 whenthe instructions are complete.

The credited media monitoring data is combined with the people meterdata using timestamps to align the two data sources to matchdemographics and audience size data to the credited media exposures.

FIG. 7 is a block diagram of an example processor platform 700 capableof executing the instructions of FIGS. 4, 5, and 6 to implement themedia identifying meter 106, 112 of FIGS. 1 and 2 and the spillovermanager 102 of FIGS. 1 and 3. The processor platform 700 can be, forexample, a server, a personal computer, a mobile device (e.g., a cellphone, a smart phone, a tablet such as an iPad™), a personal digitalassistant (PDA), an Internet appliance, a DVD player, a CD player, adigital video recorder, a Blu-ray player, a gaming console, a personalvideo recorder, a set top box, or any other type of computing device.

The processor platform 700 of the illustrated example includes aprocessor 712. The processor 712 of the illustrated example is hardware.For example, the processor 712 can be implemented by one or moreintegrated circuits, logic circuits, microprocessors or controllers fromany desired family or manufacturer.

The processor 712 of the illustrated example includes a local memory 713(e.g., a cache). The processor 712 of the illustrated example is incommunication with a main memory including a volatile memory 714 and anon-volatile memory 716 via a bus 718. The volatile memory 714 may beimplemented by Synchronous Dynamic Random Access Memory (SDRAM), DynamicRandom Access Memory (DRAM), RAMBUS Dynamic Random Access Memory (RDRAM)and/or any other type of random access memory device. The non-volatilememory 716 may be implemented by flash memory and/or any other desiredtype of memory device. Access to the main memory 714, 716 is controlledby a memory controller.

The processor platform 700 of the illustrated example also includes aninterface circuit 720. The interface circuit 720 may be implemented byany type of interface standard, such as an Ethernet interface, auniversal serial bus (USB), and/or a PCI express interface.

In the illustrated example, one or more input devices 722 are connectedto the interface circuit 720. The input device(s) 722 permit a user toenter data and commands into the processor 712. The input device(s) canbe implemented by, for example, an audio sensor, a microphone, a camera(still or video), a keyboard, a button, a mouse, a touchscreen, atrack-pad, a trackball, isopoint and/or a voice recognition system.

One or more output devices 724 are also connected to the interfacecircuit 720 of the illustrated example. The output devices 724 can beimplemented, for example, by display devices (e.g., a light emittingdiode (LED), an organic light emitting diode (OLED), a liquid crystaldisplay, a cathode ray tube display (CRT), a touchscreen, a tactileoutput device, a light emitting diode (LED), a printer and/or speakers).The interface circuit 720 of the illustrated example, thus, typicallyincludes a graphics driver card.

The interface circuit 720 of the illustrated example also includes acommunication device such as a transmitter, a receiver, a transceiver, amodem and/or network interface card to facilitate exchange of data withexternal machines (e.g., computing devices of any kind) via a network726 (e.g., an Ethernet connection, a digital subscriber line (DSL), atelephone line, coaxial cable, a cellular telephone system, etc.).

The processor platform 700 of the illustrated example also includes oneor more mass storage devices 728 for storing software and/or data.Examples of such mass storage devices 728 include floppy disk drives,hard drive disks, compact disk drives, Blu-ray disk drives, RAIDsystems, and digital versatile disk (DVD) drives.

The coded instructions 732 of FIGS. 4, 5, and 6 may be stored in themass storage device 728, in the volatile memory 714, in the non-volatilememory 716, and/or on a removable tangible computer readable storagemedium such as a CD or DVD.

Although certain example methods, apparatus and articles of manufacturehave been described herein, the scope of coverage of this patent is notlimited thereto. On the contrary, this patent covers all methods,apparatus and articles of manufacture fairly falling within the scope ofthe claims of this patent.

What is claimed is:
 1. A method to reduce spillover in a media measuringsystem, comprising: identifying media associated with media monitoringdata, the media monitoring data being received from a first meterassociated with a first media presentation device; identifying anexpected sound pressure level associated with the first meter; comparingthe expected sound pressure level to an actual sound pressure levelcollected from the media by the first meter to determine if spilloveroccurred; and crediting the media as a media exposure if spillover didnot occur.
 2. The method of claim 1, wherein a value of the expectedsound pressure level depends on a time the media was presented at thefirst media presentation device.
 3. The method of claim 1, wherein theactual sound pressure level is calculated by taking a logarithmicmeasure of a root mean square sound pressure of an audio signalassociated with the media relative to a reference sound pressure.
 4. Themethod of claim 1, wherein comparing the expected sound pressure levelto the actual sound pressure level comprises comparing a differencebetween the expected sound pressure level and the actual sound pressurelevel to a threshold.
 5. The method of claim 1, wherein crediting themedia as the media exposure includes marking the media monitoring dataas credited.
 6. The method of claim 5, further comprising transmittingthe marked media monitoring data to a central facility.
 7. The method ofclaim 1, further comprising not crediting the media as a media exposureif spillover did occur.
 8. The method of claim 1, further comprising, ifspillover did occur, discarding the media monitoring data associatedwith the spillover.
 9. The method of claim 1, further comprising, ifspillover did occur, marking the media monitoring data associated withthe spillover as not credited.
 10. A spillover manager to reducespillover in a media measuring system, comprising: a sound pressurelevel comparator to: identify an expected sound pressure level for mediaassociated with media monitoring data received from a meter associatedwith a media presentation device; and compare the expected soundpressure level to an actual sound pressure level to determine ifspillover occurred, the actual sound pressure level based on the mediadetected by the meter; and a media creditor to: credit the media with anexposure if spillover did not occur; and not credit the media with theexposure if spillover did occur.
 11. The spillover manager of claim 10,wherein the expected sound pressure level depends on a time the mediawas presented at the first media presentation device.
 12. The spillovermanager of claim 10, wherein the meter is to calculate the actual soundpressure level by taking a logarithmic measure of a root mean squaresound pressure of an audio signal associated with the media relative toa reference sound pressure.
 13. The spillover manager of claim 10,wherein the sound pressure level comparator is to compare the expectedsound pressure level to the actual sound pressure level by comparing adifference between the expected sound pressure level and the actualsound pressure level to a threshold.
 14. The spillover manager of claim10, wherein to credit the media with the exposure, the media creditor isto mark the media monitoring data as credited.
 15. The spillover managerof claim 14, further comprising a transmitter to transmit the markedmedia monitoring data to a central facility.
 16. The spillover managerof claim 10, wherein the media creditor is to discard the mediamonitoring data if spillover did occur.
 17. The spillover manager ofclaim 10, wherein the media creditor is to mark the media monitoringdata as not credited if spillover did occur.
 18. A tangible computerreadable storage medium comprising instructions that, when executed,cause a computing device to at least: identify media associated withmedia monitoring data, the media monitoring data being received from afirst meter associated with a first media presentation device; identifyan expected sound pressure level associated with the first meter;compare the expected sound pressure level to an actual sound pressurelevel collected from the media by the first meter to determine ifspillover occurred; and credit the media as a media exposure ifspillover did not occur.
 19. The computer readable medium of claim 18,wherein a value of the expected sound pressure level depends on a timethe media was presented at the first media presentation device.
 20. Thecomputer readable medium of claim 18, wherein the actual sound pressurelevel is calculated by taking a logarithmic measure of a root meansquare sound pressure of an audio signal associated with the mediarelative to a reference sound pressure.
 21. The computer readable mediumof claim 18, wherein comparing the expected sound pressure level to theactual sound pressure level comprises comparing a difference between theexpected sound pressure level and the actual sound pressure level to athreshold.
 22. The computer readable medium of claim 18, whereincrediting the media as the media exposure includes marking the mediamonitoring data as credited.
 23. The computer readable medium of claim22, further comprising instructions that cause the computing device totransmit the marked media monitoring data to a central facility.
 24. Thecomputer readable medium of claim 18, further comprising not creditingthe media as a media exposure if spillover did occur.
 25. The computerreadable medium of claim 18, further comprising instructions that causethe computing device to discard the media monitoring data if spilloverdid occur.
 26. The computer readable medium of claim 18, furthercomprising instructions that cause the computing device to mark themedia monitoring data as not credited if spillover did occur.